Search Results (60)

High-viscosity sodium alginate solutions (4.5% by mass, apparent viscosity 1 × 10⁴–2 × 10⁴ cP) are widely used in the preparation of hydrogels, wet spinning, and biomedical materials. Residual bubbles can cause internal voids in hydrogels, mechanical heterogeneity, fiber breakage during spinning, and reduced strength, and can severely affect the cell compatibility and clinical safety of biomaterials. Due to the difficulty of bubble migration, coalescence, and rupture in high-viscosity systems, traditional vacuum-standing degassing takes up to 24 h and is extremely inefficient, severely limiting the quality of subsequent processing. To address this issue, this study proposes a novel vacuum-assisted centrifugal recirculating degassing method for highly viscous sodium alginate solutions and aims to establish a kinetic framework for describing its overall degassing behavior. Using the number density of bubbles larger than 0.5 mm in diameter as an evaluation metric, we conducted vacuum-standing control experiments and univariate experiments with different screen mesh apertures (5, 1.5, 0.3, and 0.07 mm). We experimentally verified a continuous kinetic model of bubble number decay based on vacuum bubble expansion, centrifugally enhanced migration, and removal probability during the cycle. The results indicate that the bubble removal effect of 40 min of vacuum–centrifugal cyclic degassing is equivalent to that of 4 h of vacuum static settling, representing a 450% increase in degassing efficiency. There is an optimal range for a screen aperture, with the best degassing effect observed at 0.3 mm, achieving a bubble removal rate of 83.69%. The established kinetic model exhibits good fitting accuracy (RMSE = 0.17, MAPE = 5.9%) and can accurately predict degassing efficiency under different process conditions. This study provides a quantifiable, modelable, and optimizable process scheme for rapid degassing of high-viscosity sodium alginate solutions, and offers a theoretical reference for the development of degassing technologies for high-viscosity polysaccharide fluids. Full article

Measurable residual disease (MRD) in acute myeloid leukemia (AML) is monitored through detection of leukemia-associated phenotypic protein markers (LAPMs) in bone marrow aspirates, hindering disease real-time monitoring. We explored peripheral blood (PB), extracellular vesicle (EV)-based methods for MRD monitoring. To confirm that LAPMs are present in AML-derived EVs, EVs were isolated from OCI-AML3 cells by differential centrifugation and characterized according to their size (nanoparticle tracking analysis), morphology (transmission electron microscopy) and protein cargo (proteomic analysis and Western blot). CD14 and CD33 were detected in OCI-AML3 cells and their released EVs. To select a method to isolate EVs from the PB of AML patients, three techniques were tested: size exclusion chromatography followed by ultrafiltration (SEC-UF), Total Exosome Isolation Kit (Invitrogen) and Exo-spin™ Exosome Purification Kit (Cell Guidance Systems). SEC-UF allowed EV isolation with higher purity and less aggregates than the other techniques. LAPMs were detected in those EVs, but their presence depended on the isolation method. Finally, EVs from seven AML patients’ plasma were isolated by SEC-UF. LAPMs were identified in paired samples at diagnosis and remission, with differential expression throughout disease evolution. This proof-of-concept study highlights the possibility of real-time MRD monitoring through LAPMs’ analysis in AML patient’s circulating EVs. Full article

Introduction: Orthobiologics such as Platelet-Rich Plasma (PRP) and Injectable Platelet-Rich Fibrin (i-PRF) have emerged as promising tools in regenerative medicine. However, the lack of methodological standardization and the still limited comparative characterization between these products represent significant barriers to their optimized clinical application. This comparative laboratory study aimed to characterize and differentiate PRP and i-PRF, focusing on their cellular composition, obtained volume, and total Platelet-Derived Growth Factor (PDGF-BB) content. Materials and Methods: This study was conducted with 34 individuals meeting standard blood donation criteria. Peripheral blood samples were collected from all participants. PRP was obtained using a modified double-spin centrifugation protocol, whereas i-PRF was prepared using a modified low-speed centrifugation technique. Cellularity (platelet and leukocyte counts), final produced volume, and total PDGF-BB content were assessed using complete blood count analysis and an enzyme-linked immunosorbent assay (ELISA), respectively. Statistical analysis was performed using Linear Mixed Models (LMMs). Results: Both protocols resulted in significant increases in platelet and leukocyte concentrations compared to baseline values. PRP showed significantly higher platelet and leukocyte concentrations compared with i-PRF, as well as markedly higher PDGF-BB levels. In contrast, i-PRF yielded a substantially greater final volume and enabled a higher absolute delivery of total leukocytes, whereas PRP delivered a greater absolute number of platelets. In exploratory analyses, female sex, the presence of comorbidities, and increased abdominal circumference were associated with variations in product volume and cellular composition. Discussion: These findings indicate that PRP and i-PRF exhibit distinct biological profiles in terms of cellularity, volume, and total PDGF-BB content. Whether these laboratory differences translate into distinct clinical outcomes remains unknown. The results should therefore be viewed as hypothesis-generating: they suggest that PRP and i-PRF may not be interchangeable, and that future randomized clinical trials are needed to define product-specific indications based on the target tissue and desired biological mechanism. Full article

Electrospinning is the most widely used technique for creating nanofibers. However, the low production rate and the usage of a high-voltage setup have become obstacles to its widespread application. One effective method for creating nanofibers from a variety of materials is centrifugal spinning. This review discusses centrifugal spinning (CS) as an effective and scalable nanofiber manufacturing technology, particularly in filtration systems, and presents it as a promising alternative to existing methods, such as electrospinning. The review highlights the advantages of CS, including its high production rate, cost efficiency, and the ability to process various materials to produce nano- and microfibers. Despite its high potential, the issues associated with CS technology include the unpredictability of fiber quality, the inability to control diameters, and the need for more robust mathematical models to predict fiber characteristics. To eliminate these shortcomings and further enhance the industrial utility of centrifugally spun nanofibers in filtration, future studies should focus on improving process control, exploring a broader range of polymers, optimizing melt electrospinning, and designing more advanced nozzle profiles. Full article

Fiber actuators underpin soft robots, artificial muscles, and smart textiles. A persistent bottleneck is the fabrication of monodomain liquid crystal elastomer (LCE) microfibers with narrow size distributions while preserving axial alignment. This work establishes a melt-centrifugal spinning (MCS) route with two-step UV fixation that separates flow-induced alignment from network crosslinking. High-speed rotation creates a long extensional jet; an obliquely incident, on-the-fly UV dose at touchdown locks the director, and a post-cure consolidates the network. The obtained LCE microfiber can achieve large reversible contraction (L/L₀ = 0.56), lift a weight, and trigger the tweezers. The method produces a new approach for the fabrication of device-ready LCE actuators, establishes a general design principle for diameter control via curing sequence, and opens a practical path toward artificial muscles and flexible micro robotics. Full article

(1) Background: Platelet-rich plasma (PRP) therapy has become a cornerstone of equine regenerative medicine, yet significant methodological variability compromises reproducibility and clinical comparability. (2) Methods: This scoping review systematically mapped and analyzed peer-reviewed studies describing equine PRP preparation methods and commercial systems (2000–2024) following PRISMA-ScR guidelines. (3) Results: Twenty-four studies met the inclusion criteria, encompassing 317 horses and both manual and commercial devices. Double-spin manual protocols predominated, though centrifugation parameters, anticoagulants, and activation strategies varied widely. Methodological quality, assessed using an adapted nine-criterion framework, revealed that only 29% of studies achieved comprehensive reporting, particularly lacking platelet-yield and activation details. An additional multilingual web search identified 24 veterinary PRP kits, of which only 10 had published validation in horses, exposing a pronounced gap between marketing claims and scientific evidence. (4) Conclusions: These discrepancies underscore the need for standardized reporting, transparent characterization, and independent evaluation of PRP systems. The proposed framework aims to guide future research toward reproducible, evidence-based practices that enhance therapeutic reliability and clinical translation in equine regenerative medicine. Full article

Platelet-rich plasma (PRP) is an autologous blood-derived concentrate increasingly utilized in regenerative medicine for its ability to accelerate healing and tissue repair. PRP is broadly classified by leukocyte content, fibrin architecture, and platelet concentration, with classification systems developed to standardize characterization. Preparation methods, including single- or double-spin centrifugation and buffy coat techniques, influence the final composition of PRP, determining the relative proportions of platelets, leukocytes, plasma proteins, and extracellular vesicles. These components act synergistically, with platelets releasing growth factors (e.g., VEGF, PDGF, TGF-β) that stimulate angiogenesis and matrix synthesis, leukocytes providing immunomodulation, plasma proteins facilitating scaffolding, and exosomes regulating intercellular signaling. Mechanistically, PRP enhances tissue repair through four key pathways: platelet adhesion molecules promote hemostasis and cell recruitment; immunomodulation reduces pro-inflammatory cytokines and favors M2 macrophage polarization; angiogenesis supports vascular remodeling and nutrient delivery; and serotonin-mediated pathways contribute to analgesia. These processes establish a regenerative microenvironment that supports both structural repair and functional recovery. Clinically, PRP has been applied across multiple specialties. In orthopedics, it promotes tendon, cartilage, and bone healing in conditions such as tendinopathy and osteoarthritis. In dermatology, PRP enhances skin rejuvenation, scar remodeling, and hair restoration. Gynecology has adopted PRP for ovarian rejuvenation, endometrial repair, and vulvovaginal atrophy. In dentistry and oral surgery, PRP accelerates wound closure and osseointegration, while chronic wound care benefits from its angiogenic and anti-inflammatory effects. PRP has also favored gingival recession coverage, regeneration of intrabony periodontal defects, and sinus grafting. Although preparation heterogeneity remains a challenge, PRP offers a versatile, biologically active therapy with expanding clinical utility. Full article

Background/Objectives: Children with autism spectrum disorder (ASD) frequently experience poor compliance with oral medication due to bitterness, unpleasant taste, and unsuitable dosage forms such as large tablets or capsules. Risperidone, a widely prescribed antipsychotic for managing ASD symptoms, is particularly challenging in this regard. The present study aimed to develop a novel sucrose-based microfiber drug delivery system to improve the palatability, acceptance, and bioavailability of risperidone in pediatric patients with ASD. Methods: Risperidone was incorporated into sucrose microfibers using centrifugal spinning technology. Fiber morphology was characterized by scanning electron microscopy (SEM). Drug loading (DL), encapsulation efficiency (EE%), and disintegration time were measured. In vitro drug release and cytotoxicity assays were performed using human foreskin fibroblast cells (HFF-1). An in vivo palatability and preference study was conducted in male BALB/c mice to evaluate the acceptability of the formulation compared with a commercial risperidone oral solution. Results: SEM analysis revealed smooth, bead-free, non-porous fibers with uniform morphology and size distribution. The formulation showed a rapid disintegration time of ~3 s, DL of 30 ± 5 µg/mg, and EE% of 60 ± 10%. Approximately 50% of risperidone was released within 15 min. Cytotoxicity testing confirmed that concentrations ≤ 125 µg/mL maintained high cell metabolic activity, indicating biocompatibility. In vivo, the microfiber solution demonstrated a strong preference (93%) compared with the commercial oral solution (30%). Conclusions: Risperidone-loaded sucrose microfibers represent a promising fast-dissolving oral delivery system for children with ASD. This child-friendly formulation improves palatability and compliance while maintaining safety and drug release performance. Full article

Background: Platelet-rich fibrin (PRF) is an autologous platelet concentrate (APC) produced through blood centrifugation. Despite the development of various centrifugation systems, protocol variability continues to pose challenges in selecting the optimal method. This study investigated the effects of three different centrifuges and collection tubes on the fibrin characteristics and growth factor release in leukocyte- and platelet-rich fibrin (L-PRF) and advanced platelet-rich fibrin plus (A-PRF+). Methods: Blood samples from six healthy female volunteers were processed using three centrifuges (Duo, IntraSpin, and LMC-3000) and three collection tubes (Pyrex, A-P, and silica-coated plastic) under high- (~700× g for 12 min) and low-speed (~200× g for 8 min) protocols. Fibrin clot weight and length were assessed. Growth factor release of platelet-derived growth factor-BB (PDGF-BB) and vascular endothelial growth factor (VEGF) was quantified using ELISA. Fibrin architecture was examined via scanning electron microscopy (SEM). Results: High-speed protocols tended to produce larger clots, whereas low-speed protocols generated smaller but more biologically active matrices. The IntraSpin and Duo centrifuges yielded greater clot dimensions and higher growth factor release than the LMC-3000. While tube type had no significant effect on growth factor levels, silica-coated tubes tended to produce the largest clots. The Pyrex tubes demonstrated comparable or superior growth factor release. Conclusions: PRF quality is influenced by centrifuge design, g-force, and tube material. Low-speed protocols with certified centrifuges are recommended, and FDA-approved glass tubes may provide a reliable alternative to reduce silica-related risks. Standardization and appropriate material selection are essential for consistent, safe, and effective regenerative outcomes. Full article

The growing demand for sustainable materials has led to increased interest in biodegradable polymer fibers and nonwoven mats due to their eco-friendly characteristics and potential to reduce plastic pollution. This review highlights how mechanical properties influence the performance and suitability of biodegradable polymer fibers across diverse applications. This covers synthetic polymers such as polylactic acid (PLA), polyhydroxyalkanoates (PHAs), polycaprolactone (PCL), polyglycolic acid (PGA), and polyvinyl alcohol (PVA), as well as natural polymers including chitosan, collagen, cellulose, alginate, silk fibroin, and starch-based polymers. A range of fiber production methods is discussed, including electrospinning, centrifugal spinning, spunbonding, melt blowing, melt spinning, and wet spinning, with attention to how each technique influences tensile strength, elongation, and modulus. The review also addresses advances in composite fibers, nanoparticle incorporation, crosslinking methods, and post-processing strategies that improve mechanical behavior. In addition, mechanical testing techniques such as tensile test machine, atomic force microscopy, and dynamic mechanical analysis are examined to show how fabrication parameters influence fiber performance. This review examines the mechanical performance of biodegradable polymer fibers and fibrous mats, emphasizing their potential as sustainable alternatives to conventional materials in applications such as tissue engineering, drug delivery, medical implants, wound dressings, packaging, and filtration. Full article

Pollution by heavy metals such as lead is a major concern, since exposure to these metals can lead to various adverse health effects. In this work, nanofibers composed of CuO (CuONFs) were developed as a novel and promising material for Pb(II) adsorption. There have been no previous reports concerning the production of polyacrylonitrile nanofibers modified with copper sulfate pentahydrate, followed by calcination, to be utilized as a Pb(II) adsorbent. The nanofibers were obtained using the centrifugal spinning method and then were characterized before and after a calcination step using analytical techniques. Adsorption parameters were investigated, including pH, contact time, adsorbate concentration, and temperature. Satisfactory Pb (II) adsorption was reached at 298 K, pH 5.8, and a maximum adsorption of 151.34 mg g⁻¹ was achieved, predicted by the Hill model. The kinetic data proved that Pb (II) adsorption better fitted the pseudo-second-order model, while the Hill model was confirmed to best fit the equilibrium data. Thermodynamic parameters demonstrated that the lead adsorption was favorable, spontaneous, and exothermic. The CuONFs maintained 97.51% of their initial adsorption capacity after two adsorption/desorption cycles. The results showed that CuONFs have excellent potential as an adsorbent for Pb(II), while also showing high stability during reuse. Full article

The escalating environmental concerns associated with conventional plastic packaging have accelerated the development of sustainable alternatives, making food packaging a focus area for innovation. Bioplastics, particularly polyhydroxyalkanoates (PHAs), have emerged as potential candidates due to their biobased origin, biodegradability, and biocompatibility. PHAs stand out for their good mechanical and medium gas permeability properties, making them promising materials for food packaging applications. In parallel, zinc oxide (ZnO) nanoparticles (NPs) have gained attention for their antimicrobial properties and ability to enhance the mechanical and barrier properties of (bio)polymers. This review aims to provide a comprehensive introduction to the research on PHA/ZnO nanocomposites. It starts with the importance and current challenges of food packaging, followed by a discussion on the opportunities of bioplastics and PHAs. Next, the synthesis, properties, and application areas of ZnO NPs are discussed to introduce their potential use in (bio)plastic food packaging. Early research on PHA/ZnO nanocomposites has focused on solvent-assisted production methods, whereas novel technologies can offer additional possibilities with regard to industrial upscaling, safer or cheaper processing, or more specific incorporation of ZnO NPs in the matrix or on the surface of PHA films or fibers. Here, the use of solvent casting, melt processing, electrospinning, centrifugal fiber spinning, miniemulsion encapsulation, and ultrasonic spray coating to produce PHA/ZnO nanocomposites is explained. Finally, an overview is given of the reported effects of ZnO NP incorporation on thermal, mechanical, gas barrier, UV barrier, and antimicrobial properties in ZnO nanocomposites based on poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate). We conclude that the functionality of PHA materials can be improved by optimizing the ZnO incorporation process and the complex interplay between intrinsic ZnO NP properties, dispersion quality, matrix–filler interactions, and crystallinity. Further research regarding the antimicrobial efficiency and potential migration of ZnO NPs in food (simulants) and the End-of-Life will determine the market potential of PHA/ZnO nanocomposites as active packaging material. Full article

The present study aimed to develop a novel temperature and pressure-controlled hybrid system (Cent-Hydro) for large-scale nanofiber production. Nanofibers from a hydrophilic carrier matrix were prepared using the Cent-Hydro system. This study explores the effect of increasing working temperature on the surface tension and viscosity of polymer solutions. The Cent-Hydro system was calibrated through the process of jet formation, and spinning parameters were identified for the jet path. The formation of fingers in front of the thin liquid occurred due to Rayleigh–Taylor instability, and a lower concentration of polymer solution favoured the development of thinner and longer fingers. The critical angular velocity and initial velocity for jet formation were obtained when the balance between surface tension, centrifugal force, and viscous force was achieved. The effect of increasing rotational speed and working temperature on finger velocity and length was experimentally evaluated, concluding that an increase in working temperature increases finger velocity and length. Additionally, the effect of increasing rotational speed, polymer concentration, and working temperature on the diameter of the nanofiber was evaluated. Overall, the Cent-Hydro system presents a compelling proposition for large-scale nanofiber production, offering distinct advantages over conventional methods and paving the way for advancements in various applications. Full article

Background/Objectives: Encouraging results have been reported for Platelet-Rich Plasma (PRP) treatment for knee osteoarthritis (KOA). This study reports the efficacy and safety of a high dose of neutrophile and red-blood-cell-depleted PRP to treat patients with KOA. Methods: A total of 212 consecutive patients diagnosed with Kellgren–Lawrence (KL) grading 1–3 KOA chronic knee pain for at least 1 year were treated with three injections at 15-day intervals with a high dose of neutrophil-depleted PRP (4 billion platelets). Clinical outcomes were retrospectively recorded as the percentage of responders at 3-, 6-, and 12-month follow-up, following the OMERACT-OARSI criteria. Pain, through the VAS score and WOMAC score, was also been recorded. Results: A total of 4 mL of PRP containing 4 × 10⁹ platelets was obtained by single-spin centrifugation and injected intra-articularly into each patient with no preactivation. The overall responder rate of patients responding to the OMERACT-OARSI criteria at 3, 6, and 12 months was 68.9%, 72.7%, and 70.6%, respectively. A significant improvement in VAS and WOMAC scores at 3-, 6-, and 12-month follow-up compared to the pretreatment value (p < 0.01) was observed. The lowest VAS score was observed at 6 months overall and in all three KL-graded groups. The KL2 groups showed the best results regarding pain reduction and their WOMAC score at 6 months (p < 0.01). Conclusions: For KL1–3 KOA, a high dosage of neutrophil-depleted PRP is a successful treatment. It has long-lasting effects that last up to one year, relieves symptoms, and may slow the advancement of the disease. Full article

Background: Only one study has reported the presence of extracellular vesicles (EVs) in COPD patients’ sputum. Thus, we aimed to isolate and characterize EVs from COPD and healthy individuals’ sputum. Methods: A total of 20 spontaneous sputum samples from COPD patients (m/f: 19/1) and induced sputum samples from healthy controls (m/f: 8/2) were used for EV isolation. The sputum supernatants were resuspended in PBS, precleared by centrifugation at 800× g for 10 min at 4 °C, and passed through a 0.22 μm filter (Millipore, Burlington, MA, USA). EVs were isolated by a standard membrane affinity spin column method (exoEasy maxi kit, Qiagen, Hilden, Germany). The EVs were then characterized by assessing their morphology and size using Transmission Electron Microscopy (TEM) and determining the CD9 and CD81 EV-markers with Western blot analysis. Results: The EVs had a spherical shape and their mean diameter in the COPD patients was significantly greater than in the controls. Enrichment of the EV markers, CD9 and CD81, were detected in both the healthy and COPD individuals. Total EV-associated protein was significantly increased in the COPD patients compared to the controls. ROC analysis showed that total EV-associated protein in the sputum could be used to differentiate between the controls and COPD patients, with a sensitivity of 80% and a specificity of 70% at a cut-off point of 55.59 μg/mL (AUC = 0.8150). Conclusions: EVs were detectable in both the COPD and healthy individuals’ sputum. The ratio of EVs in the 150–200 nm range was twice as high in the COPD patients than in the controls. The COPD patients’ sputum contained increased total EV-associated protein as compared to controls, highlighting their value as a new source of specific exoproteins. Full article